/Engine/Source/Runtime/Engine/Classes/Engine/NetConnection.h
Appends the passed in data to the SendBuffer to be sent when FlushNet is called
int32 WriteBitsToSendBuffer ( const uint8 * Bits, const int32 SizeInBits, const uint8 * ExtraBits, const int32 ExtraSizeInBits, [EWriteBitsDataType](API\Runtime\Engine\Engine\UNetConnection\EWriteBitsDataType) DataType )